Build Your Own PHEV - XR-3 225 mpg DIY Plug-In Hybrid

Want a personal mobility vehicle that can carry two, get over 200 mpg, and be at home on the freeway? The answer could be XR-3, designed by Robert Q. Riley, LLC (www.rqriley.com). The drawback? You’ll have to assemble the XR-3 yourself.

The company plans to offer the plug-in hybrid XR-3 in either kit form or with plans for complete do-it-yourself construction.  While the XR-3 has a high-tech, aerodynamic appearance, Riley is quick to point out that the design focuses on existing technologies and could be assembled by anyone with average mechanical abilities and no prior experience.

The plug-in hybrid system is an example of this philosophy. The two front wheels are powered by a three-cylinder 23 horsepower diesel engine. The single rear wheel is powered by an electric motor connected to a lithium-ion battery. The only connection between the two is the pavement. This eliminates the need for the kind of complex electronic and mechanical interface found in other hybrid electric vehicles.

Phase-in between the two systems is handled by a simple throttle mechanism and dash-mounted switch for selecting the mode: battery-only, diesel-only, and hybrid. Battery-only operation provides a range of up to 40 miles. For highway travel at speeds up to 85 mph, the diesel engine alone will provide up 125 mph fuel economy. In the hybrid mode using both the diesel engine and electric motor, Riley estimates that up to 225 mpg is possible for ranges up to 80 miles.

The 1300 pound, clamshell canopy XR-3 has advanced safety features that include occupant protection and crash avoidance systems, with emphasis on the latter. The body could be constructed of carbon fiber over foam or conventional fiberglass over foam, both designed for the home craftsman.